Protecting Pacific Lamprey

This story was written by Science Applications Program Directorate Fellow, Amanda DeVleeschower. Learn more about Science Applications Program here.

Pacific Lamprey might not be the most typical fish, with their smooth, scale-less skin, eel-like body and sucking disc mouth. You wouldn't know it at first glance, but this fish has an important role in connecting people and nature. Adult Pacific Lampreys are parasitic and well-known for the sucker-like disc to cling to other animals to feed. Parasites often get a bad rap but these fish are vital to Indigenous people throughout their range and play key cultural and environmental roles.

An important source of food for tribal communities along the west coast, Pacific Lamprey are prized for their medicinal and nutrient-rich meat. These fish provide tribal communities with high energy foods during the freezing winter months, as well as, for marine mammals that tribal communities harvest and rely on. Pacific Lamprey are also important to freshwater ecosystems. During their migration from the ocean to freshwater, they transport necessary nutrients like nitrogen.

Pacific Lamprey were once widespread throughout the West Coast of North America. However, their abundance has declined due to reduced water flows, poor water quality and changing climate conditions. Increased water temperature could have a measurable impact on Pacific Lamprey causing reduced larvae growth, low quality offspring, earlier hatching and earlier development times. All these impacts are bad news for our parasitic friend and can cause a shift in their range and the species’ survival.


Tribal communities noticed the impacts of declining populations of Pacific Lamprey. In 2003, ten environmental organizations petitioned the U.S. Fish and Wildlife Service (USFWS) to list Pacific Lamprey under the Endangered Species Act (ESA).  Due to lack of information on the declines, the USFWS was unable to determine that the species warranted listing under the ESA. Tribal communities stepped in to take action. They encouraged the USFWS to develop a conservation plan for Pacific Lamprey, which is a tribal trust species.  As a tribal trust species, USFWS recognizes that this species is of cultural importance to Tribes and thus has a responsibility to protect and conserve this species through collaboration with Tribes. 

As a result of the conversations between the Tribes and the USFWS, in 2008 an effort was initiated by the USFWS to conserve and restore Pacific Lamprey outside the ESA-listing process.  The Pacific Lamprey Conservation Initiative (PLCI), was formed as a collaboration between Tribes; Federal, State, local agencies; and non-governmental agencies to conserve the Pacific Lamprey throughout its range in California, Oregon, Washington, Idaho and Alaska.

Christina Wang, a fish biologist with the U.S. Fish and Wildlife Service, made it clear how important tribal communities are in this project. “They have been involved since before the beginning of this initiative. They are engrained in this and leading and participating in all aspects of the PLCI”.

There are three components to PLCI:

The Pacific Lamprey Assessment: This assessment is conducted every 5 years where PLCI and other partners evaluate the Pacific Lamprey’s habitat conditions, distribution, abundance and various threats, including climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.

Learn more about climate change
. This information is then used to determine the risk of Pacific Lamprey throughout their U.S. range.

Conservation Agreement: In 2012, Federal, State, local natural resource agencies and Tribes agreed to a Conservation Agreement as a voluntary commitment to work collaboratively to reduce and eliminate threats to Pacific Lamprey and support traditional tribal use of this unique species. The Agreement supported the development of regional implementation plans, implementation of conservation actions, promotion of scientific research, and monitoring and evaluation of those actions. The objectives for this Agreement include everything from implementing effective public outreach to restoration of Pacific Lamprey habitat. The Agreement was revised and recommitted to in 2022.  Now over 60 partners have made a commitment to work together to reduce threats to Pacific Lamprey in the face of climate change.

Regional Implementation Plans: Within the Pacific Lamprey range in the U.S., there are 18 Regional Management Units (RMUs) used to implement local conservation actions. This division allows for a more effective use of local Tribal knowledge and better understanding of Pacific Lamprey and their habitats at a local level. A few examples include adult translocation and habitat restoration in the Upper Columbia RMU; successful breeding and release of adult Pacific Lamprey in the Snake River RMU; and Environmental DNA sampling and installation of Lamprey Passage Structures at the Oregon Coast RMU.

Through these partnerships, the U.S. Fish and Wildlife Service, Tribes and other partners will continue to better understand the uniqueness of Pacific Lamprey, identify high-priority research and conservation needs throughout their range, and share this information with partners to help conserve them.

You can learn more about the Pacific Lamprey Conservation Initiative by clicking here.

Story Tags

Climate change
Fish passage